The invention relates to a method for generating a retropulsive force on a body which under the influence of external forces and/or its own weight endeavours to take a position deviating from the desired position, said retropulsive force being derived from a force in vertical direction and exerting an increasing retropulsive transverse component on the body upon increasing deviations from the desired position.
Every object floating in water and connected to an anchor will be brought back upon displacement from the anchor by the weight of the anchor chain.
A buoy connected by a taut connection to an anchor straight therebelow will experience a retropulsive force due to the fact that the upward buoyant force acting on the buoy body then acquires a transverse component. Accordingly it is known to derive the retropulsive force from a force in vertical direction, for instance the weight of the anchor chain or from the upward force provided by the buoyancy.
When placing elongated bodies, such as piles, particularly a ramming pile, in an upright position the problem arises that the pile maintains a straight downward position as long as it has been attached to the hoisting means but acquires an unstable equilibrium as soon as the lower part touches the ground or bottom.
Above the water level and even therebelow at not too great a depth this problem may be solved by utilising guiding means or by supporting constructions at the lower part.
When ramming below the water surface at greater depths such expedients cannot be availed to any longer.
Consequently it has already been proposed, for example in Dutch Patent Applications Nos. 74.10905, 75.12023 and 75.14331 to utilise a yoke for slidably guiding the pile together with the ram in such a manner that during the ramming the cable supporting the yoke may be kept taut so that a tumbling down at the start of the ramming operation may be prevented. However the latter method incurs yet many difficulties.